Method of removing oil from evaporating systems



Aug. 2, 1927. T. SHIPLEY 20 METHOD OF REMOVING OIL FROM EVAPORATING SYSTEMS w Filed Jan.26, 1926 Patented Aug 2, 1927 UNITED. STATES! PATENT OFFICE.

'rnorrAs SHIRLEY, or YORK, PENNSYLVANIA, assreNoa r snIrLaYrArnNr con; PORATION, or rear, PENNSYLVANIA, A conronArroN or nnnAwAnn 7 METHOD OF REMOVING OIL FBOI EVAPORATING SYSTEMS.

Application ma January as, 1920. serial No. cam.

c the refrigerant into the evaporator, and

there slowly collects. This oil must from time to time be drawn oil'." The usual method heretofore has been to blow it ofi to the atmosphere through a blow down connection at the bottom of the evaporator. The'loss of refrigerant thus entailed is only one of the disadvantages. The evaporation ofliquid ammonia mixed with the oil chills the latter to the point of solidification renderl5 ing complete oil removal extremely diificult if not impossible. In fact it is'usually necessary to shut down the plant and allow the evaporator coils to warm up so that the oil will be warm enough initially to be blown out 2" before it solidifies. Oil removal by the for-v and deliver it, preferabl rator.

' ordinary ammonia system.

M to maintain the rangement descri mer standard practice thus involved heavy expense. c 7

According to the present invention,'I draw the oil from the bottom of the evaporator by means of a pump, to a closed cha'm r at evaporator pressure, or at a slightly higher ressure. This chamber has a valve controlle connection to the suction linejan'd with the evapo- After the chamber is charged with oil, and whatever liquid refrigerant accom-. panies it, the chamber is isolated from the evaporator and the refrigerant is caused to boil off slowly to the. suction line. The chamber is then isolated from the suction line as well as from the evaporator and when the oil is warm enough to flow freely it is salvaged by. draining it from the chamber to another container.

In the drawing '1 illustrate in elevation and part section the application of my mvention to an evaporatorforming part of an The brine tank is shown atxl. The evap- 4b orator consists of a liquidheader 2, a; gas

header 3 and connecting-pipes 4. The headers 2 and 3 are connected to a drum 5 which serves as a trap to prevent liquid refri rant from assing to the suction line 6 an also ipes 4 flooded. The arhed so an is merely a 'l'rnown type of evaporator and brine tank.

From the low end "of the liquid header 2 and'frbm the bottom of druin 5 there are 56 connections controlled by stop valves 7 and 'eva 8 respectively. These lead to the suction, or inlet valve 9 of a reciprocating pump 10. This may be operated-manually or otherwise. Its discharge valve 11' is connected to deliver into the bottom of a drum 12 whose top is connected by way of stop .valve 13 with the suction line 6. The drum 12 is equipped with si litglass 1.4, pressure gage 15 and valved ram connection 16.

Assuming that oil 'hasaccuxnulated in liquid header. 2 or in the bottom of drum 5 (or' in both), thevalve 7 or the valve 8 (or both) is opened, the valve 13 is opened slightly and the pump 10 is operated to transfer the oil to drum 12. It will be observed that this drum 12 is remote from the brine tank and so located that heat may readily beob'sorbed by oil in the drum. The pump 10 is ordinarily necessary because inmost plantsthere is no convenient location for the drum 12 below liquid header 2. In case of such locasure in drum 12 .about five pgunds higher,

than that in suction line 6. This retards in rum 12. Con chilledas. it would by more rapid eva oration of the refrigerant, and whilst e, refrigerant boils oif more slowly the" discu gagementzof refrigerant from the oil is more complete, because of the greater fluidityoftheoily This method saves. all the oil,-wastes no refrigerant, and does notrequire the. shutting downv of the plant. By disengagin the refrigerant fromthe oil at a contro led rate and at a'point remote-from the evaporator it is possible to efiect this disen agement at such temperature as insures uidity of the oil and ration.

What is claimed is: 1. The method of recovering oils from the evaporators of refrigerating systems,

which consists in drawing oil from the evaps consequent complete sepa- B5 ration of such'liquid refrigerant asis uently the oil is not so a orator with such liquid refrigerant as incidentall accompanies it, isolating such oil and re i erant from the evaporator at approximate y evaporator pressure",

such refrigerant to boil 0E from the oil at such restricted rate as to maintain the flllldr of the oil, and separately recovering the remote from the evaporator at approximately evaporator pressure, causing suchrefrigerant to boil off from the oil to the suction line, and finally discharging the oil.

" 3. The method of recovering oil from the evaporators of refrigerating systems includ ing a suction line which consists in pumping the oil and admixed liquid refrigerant from the evaporator; confinin'gthe oil and re frigerant at a pressure slightly above the suction pressure of the system at a point re I mote from the evaporator and there causing slow evaporation of the refrigerant and flow of the resultin va r to the suction line; and finally disc argmg the oil.

4. The combination with an evaporator and connected suction line, of a closed container; a valve controlled connection from the bottomof the evaporator to said container; means for causing oil to flow from the evaporator to said container through the last named connection; a valve controlled connection from the container to the suctio'n line and a valve controlled drain from said containen 5. The combination with an evaporator and connected suction line of a closed container; a valve controlled connection from the toprof Sflld container to the suction line;

a connection from thebottom of the evaporator to said container; a pump interposed in thelastname'd connection; and a valve controlled drain for said container.

In testimony whereof I have signed my name to this specification. THOMAS SHIPLEY. 

